A cryo-TSEM with temperature cycling capability allows deep sublimation of ice to uncover fine structures in thick cells

The scanning electron microscope (SEM) has been reassembled into a new type of cryo-electron microscope (cryo-TSEM) by installing a new cryo-transfer holder and anti-contamination trap, which allowed simultaneous acquisition of both transmission images (STEM images) and surface images (SEM images) in the frozen state. The ultimate temperatures of the holder and the trap reached − 190 °C and − 210 °C, respectively, by applying a liquid nitrogen slush. The STEM images at 30 kV were comparable to, or superior to, the images acquired with conventional transmission electron microscope (100 kV TEM) in contrast and sharpness. The unroofing method was used to observe membrane cytoskeletons instead of the frozen section and the FIB methods. Deep sublimation of ice surrounding unroofed cells by regulating temperature enabled to emerge intracellular fine structures in thick frozen cells. Hence, fine structures in the vicinity of the cell membrane such as the cytoskeleton, polyribosome chains and endoplasmic reticulum (ER) became visible. The ER was distributed as a wide, flat structure beneath the cell membrane, forming a large spatial network with tubular ER.

Direct Imaging of Lattice Planes in Atomically Precise Noble Metal Cluster Crystals Using a Conventional Transmission Electron Microscope

Imaging finer structural details of atomically precise noble metal cluster crystals has been difficult with electron microscopy, owing to their extreme beam sensitivity. Here we present a simple method whereby...

Recent advances in small-angle electron diffraction and Lorentz microscopy

We describe small-angle electron diffraction (SmAED) and Lorentz microscopy using a conventional transmission electron microscope. In SmAED, electron diffraction patterns with a wide-angular range on the order of 1 × 10−2 rad to 1 × 10−7 rad can be obtained. It is demonstrated that magnetic information of nanoscale magnetic microstructures can be obtained by Fresnel imaging, Foucault imaging and SmAED. In particular, we report magnetic microstructures associated with magnetic stripes and magnetic skyrmions revealed by Lorentz microscopy with SmAED. SmAED can be applied to the analysis of microstructures in functional materials such as dielectric, ferromagnetic and multiferroic materials.

Reducing Radiation Damage in Soft Matter with Femtosecond Timed Single-Electron Packets

We study the effects on radiation damage of using a femtosecond laser-driven, pulsed electron source in an otherwise conventional transmission electron microscope. We demonstrate precise control - at the single electron level - over the emission timing and the number of electrons emitted with each femtosecond laser pulse. We find that radiation damage is significantly reduced for such pulsed beams when compared to conventional ultralow-dose methods for the same dose rate and the same total dose. We also show that the degree of damage can be controlled by carefully varying the time between arrival of each electron at the specimen and by changing the number of electrons in each packet.<br>

Reducing Radiation Damage in Soft Matter with Femtosecond Timed Single-Electron Packets

We study the effects on radiation damage of using a femtosecond laser-driven, pulsed electron source in an otherwise conventional transmission electron microscope. We demonstrate precise control - at the single electron level - over the emission timing and the number of electrons emitted with each femtosecond laser pulse. We find that radiation damage is significantly reduced for such pulsed beams when compared to conventional ultralow-dose methods for the same dose rate and the same total dose. We also show that the degree of damage can be controlled by carefully varying the time between arrival of each electron at the specimen and by changing the number of electrons in each packet.<br>

Reducing Radiation Damage in Soft Matter with Femtosecond Timed Single-Electron Packets

We study the effects on radiation damage of using a femtosecond laser-driven, pulsed electron source in an otherwise conventional transmission electron microscope. We demonstrate precise control - at the single electron level - over the emission timing and the number of electrons emitted with each femtosecond laser pulse. We find that radiation damage is significantly reduced for such pulsed beams when compared to conventional ultralow-dose methods for the same dose rate and the same total dose. We also show that the degree of damage can be controlled by carefully varying the time between arrival of each electron at the specimen and by changing the number of electrons in each packet.<br>